Question

我想在Wifi客户端通信中询问有关我的代码的问题。我正在与Raspberry Pi作为服务器进行通信。我的代码的架构是：

主要活动：我有Handler类，我在OnCreat中启动了第一个负责建立wifi连接的Thread（Thread1）。

public class MainActivity extends AppCompatActivity {
public int serverPort = 40000;
public String serverIP = "10.177.86.212";
public WiFiConnector wifiConnection;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

editTextWE = (EditText) findViewById(R.id.editText_WE);

wifiConnection = new WiFiConnector(serverIP, serverPort);

Handler mHandler = new MyHandler();

WiFiConnector.Thread1 = new Thread(new WiFiConnector.Thread1(mHandler,true));
WiFiConnector.Thread1.start();
}

private class MyHandler extends Handler {
private byte[] bytes = null;

@Override
public void handleMessage(Message msg) {
      bytes = msg.getData().getByteArray("KEY");
      if(bytes!= null){
        for (int i = 0; i < bytes.length; i++){
            Log.d("Data received", "value " + (0xFF & bytes[i]) );
        }

        for (int i=0; i<bytes.length; i++) {
            editTextWE.setText(editTextWE.getText()+ "Server says: " + bytes.length + " "+ (0xFF & bytes[i]) + "\n");
        }
    }
}
}
}

WifiConnector类：Thread1和Thread2共享来自Main Activity的处理程序。 Thread1向Raspberry Pi发送命令让它开始发送数据。 Thread2专用于读取从服务器接收的数据。

public class WiFiConnector {

static String serverIP;
static int serverPort;
public static Thread Thread1 = null;

//Constructor
public WiFiConnector(String IP, int port) {
serverIP = IP;
serverPort = port;
}

public static class Thread1 extends Thread implements Runnable {

private Handler handler1;
boolean firsttime = false;
OutputStream out ;

public Thread1(Handler handler_1, boolean firsttime) {
this.handler1 = handler_1;
 this.firsttime = firsttime;
}

public void run() {
Socket socket = null;

try {

    //Writing to a Socket
    InetAddress serverAddress = InetAddress.getByName(serverIP);
    socket = new Socket(serverAddress, serverPort);

    out = new DataOutputStream(socket.getOutputStream());
    if(firsttime){
    //I send "B" to Raspberry to let him start sending data
    out.write("B".getBytes());
    this.fisrttime = false;
    }

    Thread2 comThread = new Thread2(socket, handler1);
    new Thread(comThread).start();

} catch (UnknownHostException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}
}
}

public static class Thread2 implements Runnable {

public Socket clientSocket;
private Handler handler_2;
public DataInputStream in;
public byte[] bytes = new byte[13];
public Message msg;

public Thread2(Socket clientSocket, Handler handler2) {
this.clientSocket = clientSocket;
this.handler_2 = handler2;
}

 public void run() {

 while (!Thread.currentThread().isInterrupted()) {

    try {

        if (Looper.myLooper() == null) {
            Looper.prepare();
        }

        this.in = new DataInputStream(clientSocket.getInputStream());
        in.readFully(bytes);

        if (in != null) {
            for (int i = 0; i < bytes.length; i++){
                Log.d("Data received", "valuewifi " + (0xFF & bytes[i]) );
            }

            msg = new Message();
            Bundle b = new Bundle();
            b.putByteArray("KEY", bytes);
            msg.setData(b);
            handler_2.sendMessage(msg);
        } else {
            Thread1 = new Thread(new Thread1(handler_2,false));
            Thread1.start();
            return;
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}
Looper.loop();
}
}
}

现在的问题是：我正确地从Raspberry Pi收到我的数据（每个包13个字节），确实：

Log.d("Data received", "valuewifi " + (0xFF & bytes[i]) );

正确打印我的值。然后我创建要发送到MainActivity中的处理程序的消息。 Bundle包含（我已验证）收到的输入流的相同值，但是在MainActivity的Handler中打印的消息：

Log.d("Data received", "value " + (0xFF & bytes[i]) );

替换每条消息的第一个字节值（我试图获得每个与RPi通信的2个包），其中66个实际上是＆＃34; B＆＃34;的ASCII码。我发送的信息是从Raspberry Pi开始发送数据。

请您知道为何会发生这种情况？非常感谢您的帮助！:)

Answer 1

好吧，我已经在Thread2中找到了

public byte[] bytes = new byte[13];

之前的运行{..}内的

in.readFully(bytes);

信息的交换完美无缺。否则，我只在MainActivity中获取从服务器收到的最后一个字节包。

有关为何会发生的任何建议？谢谢！

Android wifi：处理程序消息无法正常工作

1 个答案: